Impaction instrument for implanting an orthopaedic knee prosthesis and associated method of using the same

Abstract

An orthopaedic surgical instrument for use during a surgical procedure to implant a tibial tray into a surgically-prepared proximal end of a tibia and a femoral component into a surgically-prepared distal end of a femur is disclosed. The surgical instrument includes a metallic impaction handle and a removable polymeric impaction insert.

1 . An orthopaedic surgical instrument for use during a surgical procedure to implant a component of a knee prosthesis into a surgically-prepared knee bone of a patient, comprising:
 a polymer impaction insert having (i) a proximal surface, (ii) a distal surface that defines an impact surface of an impact head, the impact surface being sized and shaped to be positioned on an outer surface of the component of the knee prosthesis when the impaction insert is used to impact the component of the knee prosthesis, and (iii) an elongated shaft extending between the proximal surface and the impact head of the impaction insert, and   a metallic impaction handle removably secured to the impaction insert, the impaction handle having (i) an impact plate defining a proximal end of the impaction handle, the impact plate having an outer strike surface and an opposite underside surface, (ii) an opposite distal end having an opening formed therein that is sized and shaped to receive the elongated shaft of the impaction insert, and (iii) an elongated hollow body extending between the impact plate and the distal end, the elongated hollow body defining an elongated bore, the opening formed in the distal end opens into the elongated bore,   wherein when the impaction handle is secured to the impaction insert (i) the elongated shaft of the impaction handle is positioned in elongated bore of the impaction handle, and (ii) the proximal surface of the impaction insert contacts the underside surface of the strike plate.   
     
     
         2 . The orthopaedic surgical instrument of  claim 1 , wherein:
 the impaction insert further comprises an elongated spine extending outwardly from an outer surface of its elongated shaft,   the elongated hollow body of the impaction handle further comprises an elongated slot, and   the elongated spine of the impaction insert extends outwardly through the elongated slot of the impaction handle when the impaction handle is secured to the impaction insert.   
     
     
         3 . The orthopaedic surgical instrument of  claim 1 , wherein:
 an annular ring is positioned in the elongated bore of the impaction handle,   the impaction insert has an annular groove defined therein, and   the annular ring of the impaction handle is captured in the annular groove of the impaction insert so as to secure the impaction insert to the impaction handle.   
     
     
         4 . The orthopaedic surgical instrument of  claim 1 , wherein:
 the component of the knee prosthesis comprises a tibial tray, and   the impact surface of the impact head of the impaction insert being sized and shaped to be positioned on an outer surface of the tibial tray.   
     
     
         5 . The orthopaedic surgical instrument of  claim 1 , wherein:
 the component of the knee prosthesis comprises a femoral component, and   the impact surface of the impact head of the impaction insert being sized and shaped to be positioned on an outer surface of the femoral component.   
     
     
         6 . The orthopaedic surgical instrument of  claim 1 , wherein:
 an outer surface of a portion of the impaction handle between the proximal end and the distal end of the handle defines a grip that is configured to be gripped by a user during impaction of the impact plate, and   the elongated spine of the impaction insert extends through the grip when the impaction handle is secured to the impaction insert.   
     
     
         7 . The orthopaedic instrument of  claim 6 , wherein an outer surface of the elongated spine of the impaction insert extends radially outward beyond the grip of the impaction handle when the impaction handle is secured to the impaction insert. 
     
     
         8 . The orthopaedic surgical instrument of  claim 1 , wherein:
 the impaction insert is constructed of polyphenylsulfone, and   the impaction handle is constructed of stainless steel.   
     
     
         9 . A method of assembling a surgical instrument for use in installing a tibial tray of knee prosthesis onto a surgically-prepared proximal end of a patient's tibia, comprising:
 determining whether a fixed-bearing tibial tray or a mobile-bearing tibial tray is to be installed onto the surgically-prepared proximal end of the patient's tibia,   selecting (i) a fixed-bearing polymer impaction insert if it is determined that a fixed-bearing tibial tray is to be installed onto the surgically-prepared proximal end of the patient's tibia, or (ii) a mobile-bearing polymer impaction insert if it is determined that a mobile-bearing tibial tray is to be installed onto the surgically-prepared proximal end of the patient's tibia, and   securing the selected polymer impaction insert to a metallic impaction handle such that (i) an elongated shaft of the impaction insert is received into an elongated bore of the impaction handle, and (ii) an elongated spine extending outwardly from an outer surface of the elongated shaft of the impaction insert extends outwardly through an elongated slot formed in an outer surface of the impaction handle.   
     
     
         10 . The method of  claim 9 , wherein securing the selected impaction insert to the impaction handle comprises advancing the elongated shaft of the impaction insert into the elongated bore of the impaction handle such that an annular ring of the impaction handle is captured in an annular groove formed in the impaction insert. 
     
     
         11 . The method of  claim 9 , wherein:
 an outer surface of a portion of the impaction handle between a proximal end and a distal end of the handle defines a grip that is configured to be gripped by a user during impaction of the impact plate, and   securing the selected polymer impaction insert to the metallic impaction handle comprises securing the selected polymer impaction insert to the metallic impaction handle such that the elongated spine of the impaction insert extends through the grip when the impaction handle is secured to the impaction insert.   
     
     
         12 . The method of  claim 9 , wherein securing the selected polymer impaction insert to the metallic impaction handle comprises securing the selected polymer impaction insert to the metallic impaction handle such that the elongated spine extends outwardly through the elongated slot formed in an outer surface of the impaction handle along a longitudinal axis of the impaction handle.